The international prime meridian conference, Washington, October 1884 [microform] : recommendations suggested

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THE INTERNATIONAL

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PRIME MERIDIAN CONFERENCE

WASHINGTON,

OCTOBER, 1884.

RECOMMENDATIONS SUGGESTED

BY

SANDFORD FLEMING.

RESPECTFULLY SUBMITTED.

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THE INTERNATIONAL

Prime Meridian Conference

WASHINGTON,

OCTOBER, 1884.

Recommendations suggested by Mr. Sandford Fleming, with
explanatory remarks.

The Act of Congress, by the authority of which delegates from
the Governments of all nations have been summoned by the President
of the United States, defines the main purpose of the Conference,
as follows :—

“To fix on, and recommond for universal adoption, a common
“ Prime Meridian, to be used in the reckoning of longitude and in
“the regulation of time throughout the world.”

In order to facilitate the examination of the several subjects
included in the general question, I beg leave to suggest that they be
considered under the following heads, viz :—

1. The regulation of time.
2. The reckoning of longitude.
3. The adoption of a Primo Meridian.

Under these separate heads I venture to submit a series of recom-
mendations, to which the attention of the Conference is respectfully
asked.

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1—THE REGULATION OF TIME,
SUGGESTED RECOMMENDATIONS,

1, That a system of universal time be established, with the view of
facilitating synchronous scientific observations, for chronological reckon-
ings, for the purposes of trade and commerce by sea and land and for all
such uses to which it is applicable.

2. That the system be established for the common observance of all
peoples, and of such a character that it may be adopted by each separate
community, as may be found expedient.

3. That the system be based on the principle that for all terrestrial
time reckonings there be one recognized unit of measurement only, and that
all measured intervals of time be synchronous or directly related to the
one unit measure.

4, That the unit measure be the period occupied by the diurnal
revolution of the earth defined by the mean solar passage at the meridian
to be established as a time zero,

5 That the zero meridian for time reckoning be identical with the
zero of terrestrial longitudes to be established and known as the Prime
Meridian.

6. That the unit measure defined as above be held to be a day
absolute and designated a Cosmic Duy.

7. That such Cosmic Day be held as a chronological date, changing
with the mean solar passage at the Prime Meridian.

8. That all divisions and multiples of the Cosmic Day be known as
Cosmic Time.

9. That the Cosmic Day be divided into hours, numbered in a single
series, one to twenty-four (1 to 24). Note.—As an alternative means of
distinguishing the cosmic hours from the hours in local reckonings, they
may be denoted by the letters of the alphabet, which, omitting I and V,
are twenty-four in number,

10, That the hours of the Cosmic Day be sub-divided, as ordinary
hours, into minutes and seconds.

11. That, until Cosmic Time be admitted as the recognized means of
reckoning in the ordinary affairs of life, it is advisable to assimilate the
system to present usages and to provide for the easy translation of local
reckonings into Cosmic Time, and vice versa.

12. That all local reckonings be based on a known interval in advance
or behind Cosmic Time.

13. That the surface of the globe be divided by twenty-four equidistant
hour meridians, corresponding with the hours of the Cosmic Day.

14. That, as far as practicable, the several hour meridians be taken
according to the longitude of the locality, to regulate local reckonings.

15. That, in all cases where an hour meridian is adopted as the
standard for regulating local reckonings, the civil day shall be held to
commence twelve hours before and end twelve hours after the mean solar
passage of such hour meridian,

16. That the civil day, based on the twelve hour meridian (180° from
the Prime Meridian), shall coincide and be one with the Cosmic Day.

17. That the system of Cosmic Time being accepted, it is advisable that
it be acted upon by all civilized nations with ag little delay as possible,

REMARKS,

The determination of a Prime Meridian, common to all nations,
will admit of the establishment of a system of computing time
satisfactory equally to our reason and our necessities.

At present we are without such a system. The mode of notation
followed by common usage for time immemorial, whatever its ap-
plicability to limited areas, when extended to a vast continent, with
a network of lines of railway and telegrarh, has led to confusion
and created many difficulties. Further, it is insufficient for the
purposes of scientific investigation, so marked a feature of modern
inquiry.

Taking the globe as a whole, it is not now possit.. »recisely to
define when a year or a month or a week begins, There is no such
interval of time as the universally defined .. » everywhere in-
variable, By our accepted definiti 4 day is local ; it is limited to
a single meridian. Atsome poin.: ‘he earth’s surface one day

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is always at its commencement and another always ending. Thus
while the earth makes one diurnal revolution, we have continually
many days in different stages of progress on our planet.

Necessarily the hours and minutes partake of this normal irregu-
larity, Clocks, the most perfect in mechanism, disagree if they
differ in longitude. Indeed, if clocks are set to true time, as it is
now designated, they must, as a theory, vary not only in the same
state and county, but to some extent in the same city.

As we contemplate the general advance in knowledge, we cannot
but feel surprised that these ambiguities and anomalies should be
found, especially as they have been so long known and felt, In the
early conditions of the human race, when existence was free from
the complications which civilization has led to; in the days when
tribes followed pastoral pursuits and each community was isolated
from the other; when commerce was confined to few cities, and
intercommunicatien between distant countries rare and difficult ;
in those days there was no requirement for a common system of
uniform time, No inconvenience was felt in each lovality having
its own separate and distinct reckoning. But the conditions under
which we live are no longer the same, The application of science
to the means of locomotion and to the instantaneous transmission of
thought and speech have gradually contracted space and annihilated
distance, The whole world is drawn into immediate neighbourhood
and near relationship, and we have now become sensible to incon-
veniences and to many disturbing influences in our reckoning of
time utterly unknown and even unthought of afew generations
back, It is also quite manifest that as civilization advances such
evils must greatly increase rather than be lessened, and that the
true remedy lies in changing our traditional usages in respect to
the notation of days and hours, whatever shock it may give to old
customs and the prejudices engendered by thom.

In countries of limited extent, the difficulty is easily grappled
with, By general understanding, an arrangement affecting the
particular community may be observed and the false principles
which have led to the differencos and disagrcoments can be set
aside, In Great Britain the time of the Observatory at Greenwich

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is adopted for general use, But this involves a departure from the
principles by which time is locally determined, and hence, if the
principle be not wrong, every clock in the United Kingdon, oxcepi
those on a line due north and south from Greenwich, must of neces-
sity be in error.

On the continent of North America, efforts kisi recently been
made to adjust the difficulty. The steps taken have been, in a high
degree successful in providing a remedy for the disturbing influen-
ces referred to and, at the same time, they are in harmony with
principles the soundness of which is indisputable.

When we examine into time in tho abstract, the conviction is
forced upon us that it bears no resemblance to uny one matter or
essence which comes before our senses; it is immaterial, without
form, without substance, without spiritual essence. It is neither
solid, liquid nor gaseous. Yet it is capable of measurement with
the closest precision, eless, it may be doubted if anything
measurable could be computed on principles more erroneous than
those which now prevail with regard to it.

What course do we follow in reckoning time ? Our system implies
that there are innumerable conceptions designated “time.” “We
speak of solar, astronomical, nautical and civil time, of apparent
and mean time. Moreover, we assign to every individual point
-around the surface of the earth, separate and distinct time in this
variety. The usages inherited by us imply that there is an infinite
number of times. Is not all this inconsistent with reason and at
variance with the cardinal truth, that there is one time only ?

Time may be compared toa great stream forever flowing onward.
To us, nature in its widest amplitude is a unity. We have but one
earth, but one universe, whatever its myriad component parts. That
there is also but one flow of time is consistent with the plain dictates
of our understanding. That there can be more than one passage of
time is inconceivable.

From every consideration, it is evident that the day has arrived
when our method of time reckoning should be reformed. The con-
ditions of modern civilization demand that a comprehersive system
should be established, embodying the principle that time is one

abstract conception, and that all definite portions of it should be
based on, or be related to, one unit measure,

On these grounds I foel justified in respectfully asking the con-
sideration of the Conference to the series of recommendations which
I venture to submit,

The matter is undoubtedly one in which every civilized nation
is interested. Indeed it may be said that more or less every
human being is concerned in it, The problem is of universal im-
portance, and its solution can alone be found in the general adoption
ot a system grounded on principles recognized as incontrovertible,

Such principles are embodied in the suggested recommend:..ions,
They involve, as an essential requirement, the determination ot a
unit of ‘measurement, and it is obvious that such a unit must have
its origin in the motion of the heavenly bodies, No motion is more
uniform than the motion of the earth on its axis, This diurnal
revolution admits of the most delicate measurement, and in all res-
pects is the most available for a unit measure. It furnishes adivision
of time, definite and precise, and one which, without difficulty, can
be made plain and manifest.

A revolution of the earth, denoted by the mean solar passage at
the Prime Meridian, will be recognizable by the whole world as a
period of time common to all. general agreement this period
may be regarded as the common unit by which time may be every-
where measured for every purpose in science, in commerce and in
every-day life.

The aim of the scheme set forth in the recommendatixas is to estab-
lish a sound, rational system of notation, which «ventnally may be-
come universal, and by which, everywhoro, at the same time, the
same instant, may be observed. But, in the inauguration of a scheme
affecting so many individuals, it is desirable not to interfere with
prevailing customs more than necessary, Such influences as arise
from habit are powerful and cannot be ignored. The fact must be
recognized, that it will be difficult, immediately, to change the
usages to which the mass of mon have teen accustomed. In daily
life we are in the habit of eating, sleeping and following the routine
of our existence at certain periods of the day. We are familiar with

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the numbers of the hours by which these periods are known, and,
doubtless, there will be many who will seo little reason in any at-
tempt to alter their nomenclature ; especially those who take little
note of cause and effect, and who, with difficulty, understand the
nocessity of a remedy to some marked irregularity which, how-
ever generally objectionable, does not bear heavily upon them indi-
vidually,

For the present, therefore, we must adapt, as best we are able, tho
new system to the habits of men and women, as we find them. Pro-
vision for such adaptation is made in the series of recommendations
(see 11, 12, 13, 14, 15 and 16) by which, while local reckoning
would be based on the principles laid down, the hours and their num-
bers need not aypreciably vary from those with which we are fa-
miliar, Thus, time-reckoning in all ordinary affairs in every
locality may be made to harmonize with the goneral system.

Standard time throughout the United States and Canada has been
established in accord with this principle. Its adoption has proved the
advantages which may be attained generally by the same means.
On all sides these advantages have been widely appreciated, and
no change go intimately bearing upon common life was ever so
unanimously accepted, Certainly, it is an important step towards
the establishment of one system of Universal Time, or, as it is
designated in the recommendations, Cosmic Timo.

The alacrity and unanimity with which the chango has been
accepted in North America, encourages the belief that the introduc-
tion of Cosmic Time in every day life is not unattainable. The
intelligence of the people will not fail to discover, before long, that
the adoption of correct principles of time-reckoning will in no way
change or seriously affect the habits they have been accustomed
to. It will certainly sweep away nothing valuable to them. The
sun will rise and set to regulate our social affairs, All classes will
soon learn to understand the hour of noon, whatever the number on
the dial, whether six, as in scriptural times, or twelve, or
eighteen or any other number People will get up and retire to bed,
begin and end work, take breakfast and dinner in the same periods
of ba day as at present, and our social habits and customs will re-

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main without a change, depending, as now, on the daily returning
phenomena of light and darkness.

The one alteration will be in the notation of the hours, so as to
secure uniformity in every longitude. It is to be expected that
this chango will at first create some bewilderment, and that
it will be somewhat difficult to be understood by the masses.
The causes tor such a change to many will appear insufficient or
fanciful. In a few years, however, this feeling must pass away and
the advantages to be gained will become so manifest that I do not
doubt Cosmic or Universal Time will eventually com:nend itself to
general favour and be adopted in all the affairs of life.

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ete lenin =.

2.—THE RECKONING OF LONGITUDE.

SUGGESTED RECOMMENDATIONS,

1. That the surface of the globe being divided by twenty four equi-
distant meridians (fifteen degrees apart) corresponding with the hours
of the Cosmic Day, it is advisable that longitude be reckoned according
to these hour meridians.

2. That divisions of longitude less than an hour (fifteen degrees) be
reckoned in minutes and seconds,

3. That longitude be reckoned continuously from cast to west, begin-
ning with the Prime Meridian as zero.

4. That longitude, generally, be denoted by the same terms as those
applied to Cosmic Time.

REMARKS.

v Longitude and time thus determined become so intimately related
that they may be expressed by acommon notation. Longitude is |
simply the angle formed by two planes passing through the earth’s
axis, while time is the period occupied by the earth in revolving
through that angle. If we adopt the system of measuring time by
the revolution of the earth from a recognized zero, viz., the Prime «
Meridian, one of these planes, that through the Prime Meridian,
becomes fixed ; the other, that through the meridian of the place

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being movable, the longitudinal angle is variable. Obviously the
variable angle ought to be measured from the fixed plane as ~
and as the motion of the earth by which the equivalent time = th-
angle is measured is continuous, the longitude ought to be recko’ i
continuously in the one direction. The direction is determinec y
the notation of the hour meridians, viz., from east to west.

If longitude be so reckoned and denoted by the terms used in the
notation of Cosmic Time, the time of day everywhere throughout the
globe would invariably denote the precise longitude of the place
directly undor the (mean) sun. Conversely, at the epoch of mean
solar passage at any place, the longitude being known, Cosmic Time
would be one and the same with the longitude of the place.

The advantages of such a system of reckoning and nomenclature,
as suggested in the recommendations, are self-evident.

ate ne 0.

3.—THE ADOPTION OF A PRIME MERIDIAN.
SUGGESTED RECOMMENDATION.

1, That the meridian, twelve hours (180°), from the Observatory at
Greenwich, be adopted as the Prime Meridian to be universally used by
all peoples as the common zero in reckoning time and longitude.

REMARKS.

So far as the principles on which Cosmic Time is proposed to be
established, it is unimportant at what point or in what hemisphore
the Prime Meridian may be projected.

But the establishment of a Prime Meridian, to be recognized as
acommon zero of longitude and time, affects ail civilized people,
and interests of great importance have to be consulted in its deter-

| mination.

Among the papers laid on the table will be found one on this
subject, to which I beg leave to refer.* This paper was read before
the Canadian Institute in 16579, and it expresses the views I now

' hold.

ees,

* Longitude and Time-Reckoning.—A few words on the selection of a Prime
Meridian, to be common to all nations, in connection with time-reckoning.

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There are weighty reasons that Greenwich should be the zero of
longitude, but the Prime Meridian would be the separating line on
the surface of the globe, between two consecutive diurnal revolu-
tions, and consequently between two Cosmic dates. It is obvious,
therefore, that the selection of Greenwich as Prime Meridian would
throw the commencement of one date and the close of another in
the middle of man’s ordinary working hours, This would be ob-
jectionable, not in England only, but likewise throughout Europe.

The zero meridian should undoubtedly be removed from the
masses of population and, looking to the future, away from anv con-
siderable extent of habitable land. We should keep in view the
desirability of all mankind reckoning by concurrent dates.

The International Geodetic Congress at Rome proposed that all
Governments should adopt Greenwich as tho initial meridian, and
that longitude should be reckoned from this meridian, as a zero,
running in one direction from east to west. If longitude be con-
sidered apart, the wisdom of the recommendation must on all sides
be acknowledged.

But if the reckoning of time is to be considered, -~» cannot ignore
the reasons advanced in favour of a Prime Meridiuu being estab-
lished in another part of the globe. Tho meridian exactly 180° from
Greenwich has been suggested. This proposal has the support of M.
Otto Struve, Director of the Imperial Observatory at Pulkova, and
others. From the first I have held this view, and I can find no
argui vent which has such weight as to lead me to set it aside. In
my humble judgment I consider that the Cosmic Day should com-
mence when the sun passes the anti-meridian of Greenwieh. The
Astronomer Royal of England, Mr. Christie (10th December, 1883),
expresses his preference for this commencement of the day, and he
remarks that in proposing it to tho Committee he received the
support of M. Faye, on the part of France.

For these reasons the view which I respectfully beg leave to offer
is that the Prime Meridian should be established twelve hours
(180°) trom the Greenwich meridian.

If this recommendation be sustained, Greenwich civil time will
become identical with Cosmic Time.